> Krishna to Arjuna, "Don't think only your prescribed duty of fighting is defective. The work of a Brahmana also has defects. Even fire is covered by smoke. Even though superficially your prescribed duty may appear inferior to that of a brahmana's, you won't incur sin by doing your own prescribed duty. Therefore it is better to perform one's prescribed duty which is born of one's own nature. It is dangerous to perform another's prescribed duty even though if it's perfectly done. All activities are on the modes of nature, so there will always be some fault, one shouldn't worry about that"
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> Bhagavad Gita, Chapter#18
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Even fire is covered by smoke what to speak of activities done with other lower elements?